1H: Content-type: text/plain; charset=us-ascii
1H: Content-disposition: inline
1T: This is a
1T:   test message!
2H: Content-type: application/postscript
2H: Content-transfer-encoding: base64
2H: Content-disposition: attachment; filename="a.ps"
2B: #!PS
100 100 moveto 300 300 lineto stroke
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